Mercurial > sdl-ios-xcode
view docs/man3/SDL_DisplayFormatAlpha.3 @ 3191:91b335df6fc8
Fixed bug #750
Since many different event structures include windowID it should be placed near
the beginning of the structure (preferably right after type) so it's position
is the same between different events.
This is to avoid code like this:
if (event.type == SDL_WINDOWEVENT)
win = event.window.windowID;
else if ((SDL_EVENTMASK(event.type) & SDL_KEYEVENTMASK) != 0)
win = event.key.windowID;
else if (event.type == SDL_TEXTINPUT)
win = event.text.windowID;
else if (event.type == SDL_MOUSEMOTION)
win = event.motion.windowID;
else if ((SDL_EVENTMASK(event.type) & (SDL_MOUBUTTONDOWNMASK |
SDL_MOUBUTTONUPMASK)) != 0)
win = event.button.windowID;
else if (event.type == SDL_MOUSEWHEEL)
win = event.wheel.windowID;
...
in favor of:
win = event.window.windowID;
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 10 Jun 2009 14:00:21 +0000 |
| parents | 546f7c1eb755 |
| children | 1238da4a7112 |
line wrap: on
line source
.TH "SDL_DisplayFormatAlpha" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_DisplayFormatAlpha \- Convert a surface to the display format .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBSDL_Surface *\fBSDL_DisplayFormatAlpha\fP\fR(\fBSDL_Surface *surface\fR); .SH "DESCRIPTION" .PP This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer plus an alpha channel, suitable for fast blitting onto the display surface\&. It calls \fISDL_ConvertSurface\fR .PP If you want to take advantage of hardware colorkey or alpha blit acceleration, you should set the colorkey and alpha value before calling this function\&. .PP This function can be used to convert a colourkey to an alpha channel, if the \fBSDL_SRCCOLORKEY\fP flag is set on the surface\&. The generated surface will then be transparent (alpha=0) where the pixels match the colourkey, and opaque (alpha=255) elsewhere\&. .SH "RETURN VALUE" .PP If the conversion fails or runs out of memory, it returns \fBNULL\fR .SH "SEE ALSO" .PP \fISDL_ConvertSurface\fR, \fISDL_SetAlpha\fR, \fISDL_SetColorKey\fR, \fISDL_DisplayFormat\fR, \fISDL_Surface\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01